Facebook CEO Mark Zuckerberg is reportedly planning on making his second visit to China as the world’s biggest social networking company continues to look for the best way to expand into the country that holds the world’s biggest Internet population.

Despite earlier reports that Facebook CEO Mark Zuckerberg and Chief Operating Officer Sheryl Sandberg had different views about entering China, Sandberg makes it clear that they both actually agree on the importance of China. She told Reuters:

“Our company mission is really clear, which is we want to connect the whole world, and it’s impossible to think about connecting the whole world right now without also connecting China.”

China is currently the world’s largest Internet market by user volume, and despite Facebook being blocked in the country, it’s a hard market to ignore. Zuckerberg visited China in December and met with the heads of Chinese Internet companies including Baidu, Sina and Alibaba, which sparked speculation on a partnership with a local Chinese Internet firm to operate in the country.

Sandberg said the timing and the agenda of the trip was undetermined, but that Zuckerberg, who is currently studying Chinese, would probably return this year.

In the same report, Sandberg also described a public offering of Facebook shares as “inevitable,” without providing details on when Facebook expects to have an IPO.

“It’s a process that all companies go through. It’s an inevitable process for us, the next thing that happens,” she said. “No one is buying us, we’re going public.”

Sandberg said the LinkedIn IPO, whose shares more than doubled after making its debut as a publicly traded company, validated the importance of the business behind social networking.

According to market research firm eMarketer, Facebook is expected to generate roughly $4 billion in advertising revenue in 2011, up from $1.86 billion a year earlier, not to mention hopes of amassing one billion users within the year. Entry to China and funds from an IPO would definitely help the social network achieve that.